1. Field of the Invention
This invention relates generally to outdrives for small marine craft, and more particularly to a kit for adapting a surface type drive to small, hallow draft fishing craft for operation in very shallow water.
2. General Background
Small marine craft are generally powered by outboard motors generally comprising a portable, unitary structure including a power head incorporating an internal combustion engine. Such engines have a drive shaft extending vertically from the power head to a lower unit transmission gear for coupling to a horizontal propeller shaft. The unitary unit is suspended from the boat's transom in such a manner that the propeller is totally submerged below the boat's keel.
Somewhat larger marine craft having deeper drafts have the option of inboard propulsion drives which utilize submerged or surface breaking propellers. Their deeper draft allows for mounting the engine's transmission either inboard or outboard. In either case, the transom must be greater than that usually associated with small, shallow draft boats. Most such drives are efficient, high performance systems used for heavy loads and/or high speed.
There is, however, a need for a propulsion unit which will allow small, shallow draft boats to travel at low speed in very shallow water. Since most outdrive systems are expensive and complicated, as is illustrated by U.S. Pat. Nos. 4,976,638, 4,775,342, 5,279,509, 3,933,116, and 5,326,294, and require expert installation, there is a need for an uncomplicated, easily installable inboard-outdrive for small craft such as small flat bottom fishing boats. Through transom direct drives such as that disclosed by U.S. Pat. Nos. 4,976,638, 4,544,362, and 4,645,463 provide a more simplified drive in the form of a pivotal ball joint, these drives are still expensive due to their special pivotal joints and cast housing. Therefore, there is still a need for a simple, inexpensive outdrive which can be installed by the average person on most small fishing boats.